I. Field of the Invention
This invention relates to a fuel cell generator control system which, in response to the occurrence of an abnormal condition, controls a safety operation to protect the fuel cell generator from damage. At the same time, the present invention is simple in construction and low in power consumption.
II. Background Information
A plant device including a fuel cell generator is generally designed so that, when a abnormal condition takes place therein, the device carries out a predetermined operation to protect itself and people near the device. Generally, to achieve this result two systems each comprising a plant body, a control equipment section for controlling the operation of the plant body, and a power source equipment section for supplying electric power to the control equipment section are provided for the plant device. The two systems are operated in such a manner that one of the systems is always operating. However, when one system malfunctions, the other system is put into operation, so that the plant is in operation at all times. Thus, continuous operation of the plant may be achieved for all the essential devices forming the plant by replacing the essential devices with backup devices when malfunctions occur. For example, when the power source equipment section malfunctions, then that section is replaced by a secondary battery which has been floating-charged by the section. When an abnormal condition occurs in the plant device, the operator is protected from hazards and the plant device is protected from damage. However, this method causes the plant device to become complex and large in scale, with the result that power consumption is increased accordingly. Hereinafter, the operation of the plant device which is carried out to protect the plant device and the people nearby will be referred to as the "safety operation," when applicable.